Tailoring Ultrasonic Waves through Phase-Controlled Optical Generation

Tailoring Ultrasonic Waves through Phase-Controlled Optical Generation

Supervisor : Olga Boyko
Contact : Olga.Boyko@insp.jussieu.fr
Funding : INSP/Sorbonne Université
keywords : Experimental, Internship M2, Nano Photo-Phononics, and Proposed thesis
Gratification : Oui
Team(s) internship page(s) : Acoustics and optics for nanosciences and quantum physics
Internship description
  • Scientific description: The aim of this master’s level internship is to advance a picosecond
    ultrasonics setup by incorporating a Spatial Light Modulator (SLM) into the optical excitation
    pathway. This novel integration will allow the precise generation and control of Surface
    Acoustic Waves (SAWs) on unstructured, flat surfaces by modulating the phase of ultrafast
    laser pulses. The project offers a unique opportunity for the intern to work at the
    intersection of ultrafast optics, acoustics, and photonics, contributing to cutting-edge
    advancements in acoustic signal processing, materials characterization, and wavefront
    engineering.
  • Background: Surface Acoustic Waves (SAWs) are critical in a wide range of applications, from
    sensors and non-destructive testing to advanced communication technologies. Traditional
    methods for generating SAWs involve the use of custom-fabricated nanostructures to define
    specific wavefronts and spatial distributions. However, these methods are rigid, labor-
    intensive, and costly. By introducing phase modulation through a Spatial Light Modulator
    (SLM), it is now possible to generate reconfigurable, complex SAW patterns without the
    need for physically altering the sample surface. This new approach enables dynamic control
    over the spatial and spectral characteristics of the SAWs, allowing for more flexible and
    efficient testing of material properties.
  • Project Scope. During the internship, the student will engage in the following tasks:
    • 1. System Integration: The intern will integrate the SLM into an existing picosecond
      ultrasonics setup, optimizing the alignment and phase modulation parameters for
      precise control over the laser-induced SAWs.
      2. Phase Pattern Design: Using optical modeling software, the intern will design phase
      patterns to be encoded on the SLM. These patterns will control the spatial
      distribution of the laser excitation, enabling the generation of tailored SAW
      wavefronts, point sources, and complex displacement maps.
      3. Experimental Testing: The intern will conduct experiments to generate and
      characterize SAWs on various flat, unstructured surfaces. Through this work, the
      student will explore different wavevector configurations to study SAW dispersion
      relations in test samples